ICTS

I shall discuss the physics of hard probe of dense and hot matter produced in heavy ion collisions from the view point of open quantum systems.

TBA

High-energy collider processes naturally produce pairs of particles with correlated spins, providing a unique arena to study quantum entanglement at relativistic energies. In the talk, we discuss how spin correlations in processes such as heavy-quark production can be used to quantify entanglement and formulate Bell-type tests using experimentally accessible observables.

We discuss transverse momentum broadening, radiative emission and thermalisation of jets in the QGP.

I will give an overview of the study of jets in the QGP. I will cover aspects of energy loss and jet substructure.

TBA

We discuss transverse momentum broadening, radiative emission and thermalisation of jets in the QGP.

Jets produced in proton–nucleus (p+A) collisions provide a powerful probe of QCD in a nuclear environment. Measurements at RHIC and the LHC use jets to address three central questions. First, since jet-QGP interactions are expected to be small, or even absent, in p+A collisions they serve as a crucial baseline for interpreting observations in nucleus–nucleus collisions where strong jet quenching signals have been shown to exist. Second, they reveal how partons propagate through cold nuclear matter, constraining effects such as nuclear parton distribution functions and initial-state multiple scattering. Third, at forward rapidities and small momentum fractions, jet measurements probe the high-gluon-density regime where nonlinear QCD dynamics and possible gluon saturation may emerge.
In this lecture I will discuss how key results from RHIC and the LHC have collectively tested QCD in the high-density cold nuclear matter environment, sharpened the interpretation of jet quenching in heavy-ion collisions, and provide a preview of the studies to come at the future Electron–Ion Collider (EIC).

In this lecture series I will give an overview of lattice QCD studies of hot nuclear matter with emphasis on heavy flavor probes. In the first lecture I will review the lattice QCD results on the deconfinement and chiral transitions, and the equation of state. In the subsequent lectures, I will discuss the nature of heavy flavor degrees of freedom across the transition temperature, the fate of heavy quark anti-quark bound states and heavy quark diffusion.

In this talk, I'll give a brief overview of the theory of probing the internal structure of the nucleon in 3D at the upcoming electron-ion collider (EIC).

TBA

Multi-body QCD exhibits rich and complex phenomenology, notably in the Quark-Gluon Plasma (QGP) at high temperature, which is generated in nuclear collisions at RHIC and the LHC; and at high density, corresponding to low momentum fraction x in hadrons and nuclei, which can be probed by forward RHIC and LHC measurements and the future Electron-Ion Collider. These lectures will explore how we study multi-body QCD by combining experiment and theory. The focus of the first two lectures is the measurement of jet quenching, the interaction of energetic quark and gluon jets with the QGP. The third lecture discusses a comprehensive analysis of the world’s jet quenching data using Bayesian Inference enhanced by Machine Learning, to quantify the structure and dynamics of the QGP. The fourth lecture turns to many-body QCD at low x, presenting a new framework for the comprehensive analysis of Deep Inelastic Scattering and hadron collider data - likewise using ML-enhanced Bayesian Inference - to search for evidence of non-linear QCD evolution and gluon saturation.

Heavy quarks, produced in early hard scatterings in relativistic heavy-ion collisions, provide a unique probe of the early-time electromagnetic fields and the geometry of the quark–gluon plasma. In this talk, I discuss the rotational Brownian motion of heavy quark spins (semi-classical treatment) in the QCD medium and its consequences for the polarization of open heavy-flavor hadrons. Analytical expressions for both vector and tensor polarization are derived, corresponding to baryon spin polarization and vector meson spin alignment, respectively. Assuming that heavy quarks acquire initial spin polarization from the strong magnetic fields generated in off-central collisions, we study how medium interactions lead to momentum-dependent depolarization and compare the results with recent measurements of D∗+ spin alignment reported by the ALICE Collaboration. Furthermore, we introduce polarization harmonics of open heavy hadrons as a novel observable sensitive to the initial geometric anisotropies of the fireball. The resulting azimuthal modulation of heavy-flavor polarization reflects path-length dependent spin relaxation and is directly related to the initial spatial eccentricities, providing a new and complementary probe of the early-time dynamics and geometry of relativistic heavy-ion collisions.

TBA

Multi-body QCD exhibits rich and complex phenomenology, notably in the Quark-Gluon Plasma (QGP) at high temperature, which is generated in nuclear collisions at RHIC and the LHC; and at high density, corresponding to low momentum fraction x in hadrons and nuclei, which can be probed by forward RHIC and LHC measurements and the future Electron-Ion Collider. These lectures will explore how we study multi-body QCD by combining experiment and theory. The focus of the first two lectures is the measurement of jet quenching, the interaction of energetic quark and gluon jets with the QGP. The third lecture discusses a comprehensive analysis of the world’s jet quenching data using Bayesian Inference enhanced by Machine Learning, to quantify the structure and dynamics of the QGP. The fourth lecture turns to many-body QCD at low x, presenting a new framework for the comprehensive analysis of Deep Inelastic Scattering and hadron collider data - likewise using ML-enhanced Bayesian Inference - to search for evidence of non-linear QCD evolution and gluon saturation.

Heavy quark systems are ideal tools to probe the physical properties of quark-gluon plasma. In this talk, I will first introduce the open system description for quantum Brownian motion. Then, it is applied to heavy quark and quarkonium in the quark-gluon plasma. Finally, I will discuss how this approach can be used to describe heavy quarks near the QCD critical point.

Multi-body QCD exhibits rich and complex phenomenology, notably in the Quark-Gluon Plasma (QGP) at high temperature, which is generated in nuclear collisions at RHIC and the LHC; and at high density, corresponding to low momentum fraction x in hadrons and nuclei, which can be probed by forward RHIC and LHC measurements and the future Electron-Ion Collider. These lectures will explore how we study multi-body QCD by combining experiment and theory. The focus of the first two lectures is the measurement of jet quenching, the interaction of energetic quark and gluon jets with the QGP. The third lecture discusses a comprehensive analysis of the world’s jet quenching data using Bayesian Inference enhanced by Machine Learning, to quantify the structure and dynamics of the QGP. The fourth lecture turns to many-body QCD at low x, presenting a new framework for the comprehensive analysis of Deep Inelastic Scattering and hadron collider data - likewise using ML-enhanced Bayesian Inference - to search for evidence of non-linear QCD evolution and gluon saturation.

In this talk, I will discuss the complex heavy-quark potential in an anisotropic quark-gluon plasma using kinetic theory with a Bhatnagar-Gross-Krook collision kernel to incorporate collisions via gluon collective modes. By modifying the medium's dielectric permittivity with momentum anisotropy and finite collisional rates, we derive both the real and imaginary components of the potential. While collisions have minimal impact on the real part and binding energy, they significantly amplify the imaginary part, modulating the effects of anisotropy. Most importantly, the Weibel instability in momentum-space anisotropic plasmas is removed in the presence of collisions.

Heavy quarks are unique probes of the transport properties and hadronization of the quark–gluon plasma formed in ultra-relativistic heavy-ion collisions, but their strong coupling to the evolving medium requires a multi-ingredient approach for reliable descriptions of in-medium interactions. I will present a newly developed framework [1] that combines state-of-the-art ingredients for heavy-flavor transport in hot QCD matter. It couples lattice-QCD–constrained T-matrix based elastic scattering to relativistic Langevin dynamics with diffusion and medium-induced gluon radiation, embedded in a 2+1D viscous hydrodynamic evolution. Hadronization is evaluated with a four-momentum conserving recombination approach supplemented with fragmentation constrained by proton–proton data, followed by diffusion in the hadronic phase using the Ultra-relativistic-Quantum-Molecular-Dynamics (UrQMD) model. I will report our recent results for charm-hadron nuclear modification factors, elliptic flow, and charm hadro-chemistry ratios, and compare them to Pb–Pb data at 5 TeV from ALICE and CMS as well as Au–Au data at 200 GeV from STAR. Constraints on heavy-flavor diffusion coefficient in hot QCD matter are discussed. [1]: T. Krishna, R. Rapp, Y. Fu, S. A. Bass, and W. Ke, Phys. Lett. B 871,(2025)(139999)

Multi-body QCD exhibits rich and complex phenomenology, notably in the Quark-Gluon Plasma (QGP) at high temperature, which is generated in nuclear collisions at RHIC and the LHC; and at high density, corresponding to low momentum fraction x in hadrons and nuclei, which can be probed by forward RHIC and LHC measurements and the future Electron-Ion Collider. These lectures will explore how we study multi-body QCD by combining experiment and theory. The focus of the first two lectures is the measurement of jet quenching, the interaction of energetic quark and gluon jets with the QGP. The third lecture discusses a comprehensive analysis of the world’s jet quenching data using Bayesian Inference enhanced by Machine Learning, to quantify the structure and dynamics of the QGP. The fourth lecture turns to many-body QCD at low x, presenting a new framework for the comprehensive analysis of Deep Inelastic Scattering and hadron collider data - likewise using ML-enhanced Bayesian Inference - to search for evidence of non-linear QCD evolution and gluon saturation.

TBA

In the two lectures I will discuss detailed aspects of jet physics for hard probes and how application of machine learning is taking this field to next frontiers.

In this talk, I will talk about the non-perturbative potential between a heavy quark and an anti-quark pair in a QCD plasma at finite temperature. Extracting the leading order static potential $V_s(r)$ from the temporal Wilson line correlators we then calculate the spin dependent component $V_{ss}(r)$ at $\mathcal{O}(1/M^2)$, using color-magnetic field insertions. The computations have been performed for quenched QCD, at $1.5$ times the deconfinement temperature $T_d$, on a 4D lattice with spatial extent $N_s=68$ and temporal size $N_\tau=16, 20$. We show that $V_{ss}(r)$ develops an imaginary part at finite temperature, a similar phenomenon observed in the static potential. The spin potential at finite temperature breaks the degeneracy between pseudo-scalar and vector quarkonium states which suggests different bound state energy, thermal decay widths and dissociation temperatures.

The main focus of the talk will be how non-equilibrium aspects of hot QCD matter (the quark–gluon plasma) produced in heavy-ion collisions affect the properties of heavy quarks.